Spark-plug.



E. W. COLE.

SPARK PLUG. APPLIUATION FILED SEPT. 30, 1913.

Patented July 28, 1914.

l/VVEA/TOR T @FFlQE EMORY VJ. COLE, 9F WI'LARTDN, TEXAS.

SPARK-PLUG.

Specification of Letters Patent.

Application filed. September 30, 1913. Serial No. 792,544.

-. all whom it may concern Be it known that l. EMORY ll. Conn, a citizen of the United States, residing at Wharton, in the county of "Wharton and State of Texas, have invented certain new and useful Improvements in SparlcPlugs, of which the following is a specification.

My invention relates to improvements in spark plugs. Its objects are to decrease the possibility of imperfect sparking due to car-- bonization at the points, and to provide a visible indication as to whether or not the plug is properly performing its function, and to further provide means for readily ascertaining whether or not a failure of the plug to perform its function is due to carbonization or to some defect in the circuit exterior to the plug.

lVith these and various other objects in View, the invention has relation to certain novel features of construction and operation, an example of which described in the following specification and illustrated in the accompanyirur drawing, wherein:

Figure l is a View showing in side tion one form of. my inmrovcd plug. is an axial vertical serfiionid View ofthc plug, the section being then upon the line U-l.!) ot- ,l ig. 1. Fig. o a transi'erse sectional view taken upon. ti line {U-U of Fig. 2. l ies. l and are respectively top and bottom iews of the plug. l igrssll and T are respectively an elevation and a bottom View of modified term of: the plug, Fig. 8 is an axial vertical section o'l another IllOtllllC'Xr tion. Fig. 9 is transverse section ol the same taken upon the line 7/ of Fig. 8. Fig. is a bottom view of the same.

Referring now more particularly to the drawing, wherein like reference characters designate similar parts in all the figures, the numeral 1 denotes a nut having an integral, extcriorly threaded sleeve 2, which may be screwed into an engine cylinder in the usual llliilllltlt',tl1 axis of the nut and sleeve being in most cases vertical. Adjacent to its juncture with the sleeve 2, the nut 1 is formed with an interior shoulderB, upon which is adapted to rest a collar l integrally formed upon. a plug 5, ofporcelaiu or some other insulating material, The plug 5 is held rigid in its relation to the members i and 2. by an exteriorly threaded portion 6 (ii a nut 7, said portion 6 being screwed into the nut 1. Between the shoulder 3, and the collar 4,

ring of packing 8 is interposed and a siinilar ring is also interposed between said collar and the member 6. The upper portion of the central aperture of the nut T is enlarged to a somewhat greater diameter than that of the plug 5, as indicated at 9.

In the upper end of the plug 5, which preferably projects somewhat beyond the nut 7, there is embedded the rectangular lower end 10 of a binding-post 11, with which post one wire of a battery circuit may be connected as shown in Fig. 1. The other battery wire will be connected with the frameof the engine at any point, in the usual manner, this connection not being shown. There are also embedded in the plug 5 two wires 12 and 13, the former of which is' connected at its upper end with the portion 10 of the binding post 11 and at its lower end projects from the plug, forming one of the angular sparking points 14:. The lower extremity of the wire 13 forms the other sparking point, and its upper end tern'iinates at the surface of the plug 5 in a named relation to the wall of the aperture 9. The lower portion of the plug, which is disposed within the sleeve 2, preferably ipcrs gradually to the adjacent plug extremity as indicated at 15.

The modification of my invention, which is illustrated in Figs. 6 and differs from the first-described form of the device only with respect to the lower extremity of the plug, which is recessed as indicated tell'lil, the sparking points being contiguous with the top of the recess.

in that form of my device shown in Figs. 8, 9, and 10, the lower end of the plug 5 bifurcated, and the two wires 12 and 13 are passed through the fur-cations 1?. terminal; ing' in sparking points, only one of which, in this instance, is angular. Just above the furcations 17, a wire 18 encircles the tapered portion of the plug, and a wire l9, establishing connection between diametrically opposite pointsof the ring 18, is passed l)e tween the furcations. A wire 20 embedded in the plug has connection at its lower end with the ring 18 and has its upper extremity terminating at the surface of the plug preferably in the same horizontal plane as the upper end of the wire 13, the exposed ends of the two said wires being, however, considerably spaced in such a plane.

The operation of my invention. in its Various forms, will now be considered. In all three forms. when the plug is properly Patented July as, ram;

performing its function, sparking will cur in two olaces namel' between the points 14- and between the upper end of the wire '13 and the wall of the aperture 9. Since the spark in the upper portion of the plug will be readily visible, it may be easily ascertained whether any engine trouble is due to a failure of the spark plug to perform its function. If the plug is not properly performing its function, this may be due either to earbonization at the points or to a defect in the electrical circuit exterior to the plug. That form of my invention which is illustrated in Figs. 8, 9, and 10 has-the additional advantage of indicating not only a failure of the spark in the ignition chamber but also whether this failure is due to carbonization at the points or to a defect in the circuit exterior to the plug.

lVhen sullicient carbon has been deposited upon the lower end of the plug to interfere with the spark between the points 14, a

closed connection will be established by this carbon between the lower end of the wire 12 and the ring 18. The electricity will flow therefore, either wholly or in, part to the wire 20 from the lower end of the wire 12 and hence sparking will occur between the upper end of the wire 20 and the wall of the aperture 9. Therefore the appearance of a spark at this point will be a positive indication of carbonization at the sparking points, while the non-appearance of any spark in the upper portion of the plug will indicate a defect in the circuit exterior to the plug, lly recessing the sparking points as indicated in Fig. 6, the heat thrownout by the spark will be confined and concentrated in its ellect. tending to consume any carbon formed in the recess l6, and prevent a consequent short circuit between the points.

in the present practice, there is no convenient way of immediately ascertaining whether engine trouble has its origin in the spark-plug, and in M l'ing the source of the lrouble. the plug an unscrewed: from the cylinder, only to be found in perfect workii f order. This unnecessary trouble and :oss ol' time are eliminated by my invent ion.

The invention is presented as including all such nizalilicutions and changes as may properly come within the scope of the following claims.

What I claim is:

l. A. spark plug comprising an insulating member, an open-ended metallic casing receiving said member. a binding post surmounting the insulating member, a conductor forming a ring encircling the lower end of the insulating member and having contact therewith, and three conductors embedded in the insulating member, two of which project from the lower end of said member forming electrodes, and at their upper ends are respectively connected to the binding post and terminated at a sparking distance from the casing, the third conductor having connection at its lower end with said ring and terminating at its upper end a sparking distance from the casing.

2. A spark plug comprising an insulating member, an open-ended metallic casing receiving said member, a binding post surmounting the insulating member, apair of electrodes mounted upon the lower end of the insulating member, a conductor extending from one of the electrodes to said binding post, a conductor extending from the other electrode to the upper portion of the spark plug and terminating in a spaced relation to the casing, a conductor contiguously encircling the insulating member disposed above the electrodes out of sparking distance from the same, and a conductor extending from the last specified conductor to the upper extremity of the plug.

3. A spark plug comprising an insulating member, having its lower extremity bifurcated, an open ended metallic casing receiving said member, a binding post surmounting the insulating member, a pair of electrodes respectively mounted upon the furca-' 4:. A1 spark plug comprising an insulatingmom or, an open-ended casing receiving said member, a pair of electrodes mounted upon the lower end of the insulating memher, a conductor mounted upon the insulating member out of sparking distance from its electrode and conductors extending from each electrode, an accumulation of carbon upon the lower end ofv the insulating member, serving to establish connection between one of the electrodes and the adjacent conductor.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

, EMORY W. COLE Witnesses:

J. S. lllUnnAY,

JACK A. SCI-ILEY. 

